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Natural variation in fruit characteristics and seed germination of Jatropha curcas in Benin,West Africa

Authors:
  • National University of Agriculture, Republic of Benin
  • Université Nationale d'Agriculture, Bénin

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An investigation was conducted in the ten phytodistricts of Benin, West Africa, in order to assess the level of morphological variation in Jatropha curcas seed and their germination potential. Hierarchical classification of the morphological traits of seeds identified five morphotypes, using 54% of the overall morphological information. Canonical discriminant analysis performed on the five morphotypes revealed highly significant differences. Morphotype 1 included seeds from the phytodistricts of Côtier, Pobè, The Ouémé Valley, and Plateau. Morphotype 2 and Morphotype 5 seeds were from the phytodistricts of Bassila, Zou, and Borgou-Sud; while Morphotype 3 and Morphotype 4 seeds were from the phytodistricts of Borgou-Nord, the Atacora Chain, and Mekrou-Pendjari. Significant morphological variation existed within the seeds as a consequence of genetic make-up and/or environmental effects. Seed from Mekrou-Pendjari and the Atacora Chain were black, smooth, light (0.67 g seed–1), and small (1.76 cm-long and 1.15 cm-wide). Seed from Plateau, Côtier,The Ouémé Valley, and Pobè zones were brown, rough, heavy (0.84 g seed–1), and large (1.97cm-long, 1.2 cm-wide). All seed germination started 4 d after sowing and ended between day-7 and day-8. Seed germination timing varied significantly with morphotype.
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Natural variation in fruit characteristics and seed germination of
Jatropha curcas in Benin, West Africa
By E.A. PADONOU1*, B. KASSA1, A. E. ASSOGBADJO1, B. FANDOHAN1, S. CHAKEREDZA2,
R. GLÈLÈ KAKAÏ1and B. SINSIN1
1Faculty of Agronomic Sciences, University of Abomey-Calavi, 01 P. O. Box 526, Cotonou, Benin
2African Network for Agriculture, Agroforestry and Natural Resources Education, United Nations
Avenue P. O. Box 30677-00100, Nairobi, Kenya
(e-mail: padonouelie@gmail.com) (Accepted 19 July 2013)
SUMMARY
An investigation was conducted in the ten phytodistricts of Benin, West Africa, in order to assess the level of
morphological variation in Jatropha curcas seed and their germination potential. Hierarchical classification of the
morphological traits of seeds identified five morphotypes, using 54% of the overall morphological information.
Canonical discriminant analysis performed on the five morphotypes revealed highly significant differences.
Morphotype 1 included seeds from the phytodistricts of Côtier, Pobè, The Ouémé Valley, and Plateau. Morphotype 2
and Morphotype 5 seeds were from the phytodistricts of Bassila, Zou, and Borgou-Sud; while Morphotype 3 and
Morphotype 4 seeds were from the phytodistricts of Borgou-Nord, the Atacora Chain, and Mekrou-Pendjari.
Significant morphological variation existed within the seeds as a consequence of genetic make-up and/or
environmental effects. Seed from Mekrou-Pendjari and the Atacora Chain were black, smooth, light (0.67 g seed–1),
and small (1.76 cm-long and 1.15 cm-wide). Seed from Plateau,Côtier,The Ouémé Valley, and Pobè zones were brown,
rough, heavy (0.84 g seed–1), and large (1.97cm-long, 1.2 cm-wide). All seed germination started 4 d after sowing and
ended between day-7 and day-8. Seed germination timing varied significantly with morphotype.
Attempts are now being made to promote the
widespread cultivation of plants or crops previously
grown only in localised areas. Species such as Jatropha
curcas L., which can be grown for processing into
biodiesel, have captured the attention of researchers in
temperate and tropical zones.J. curcas is well-adapted to
semi-arid marginal areas. The oil from J. curcas can be
processed and used as a substitute for diesel fuel, while
growing the plant can control soil erosion (Heller, 1996;
Foidl and Elder, 1997; Subramanian et al., 2005). The
seeds, leaves, and bark of J. curcas are also used in
traditional medicine and for veterinary purposes
(Assogbadjo et al., 2009). J. curcas can be propagated by
cuttings and through seed. If propagated by seed, the
plant develops a single tap-root structure (Padonou,
2009). However,low seed viability limits the efficiency of
propagation by seed (Gadekar, 2006). When using
cuttings,no tap-root will develop and the root system will
develop into a dense and superficial carpet of
adventitious roots, suitable for preventing soil erosion
and for accumulating sediment, but vulnerable to
landslides and uprooting by wind (Padonou, 2009).
Such a multiple-use crop requires genetic
improvements to promote cultivation for oil production,
the prevention of erosion, as well as medical and
veterinary purposes. Currently, crop improvement in J.
curcas has been limited (Ginwal et al., 2005). J. curcas has
high economic importance in Benin. Indeed, J. curcas
plants were exported from Benin to France in the 1940s
for the production of household soap and were widely
used as hedges in the North of Benin in the 1990s (Global
Facilitation Unit for Underutilized Species, 2007).
However, few scientific data are available on the natural
variation in seed morphology and seed germination in this
species in Benin (Assogbadjo et al., 2008; 2009; Padonou,
2009) although J. curcas has recently been considered by
the Benin Government as a priority tree species to be
developed in agroforestry systems for bio-fuel production.
In addition, significant genetic variation exists in seed
morphology and in the oil content of Jatropha seed.This is
important for tree improvement programmes.
Unfortunately, little work has been done on germplasm
conservation (Kumar and Sharmar, 2008). Kaushik et al.
(2007) reported some variation in seed traits and oil
contents in 24 accessions of J. curcas collected in Haryana
State, India. Consequently, one important question to be
addressed was the possible link between seed morphology
and environmental factors (or phytodistricts) in Benin.
Since no information was currently available, the first
objective of the present study was to assess the level of
natural variation in seed morphology in order to identify
morphotypes of J. curcas based on seed characteristics.If
the morphological variation in seeds could be correlated
with their provenance and/or linked to their germination
parameters, it would be possible to predict which seed
provenances were most suitable for large-scale
propagation. The second objective of this study was to
compare the rates of germination and the germination
parameters of the different morphotypes of J. curcas
seed, our hypothesis being that there was a strong
correlation between the morphological variation in seed
and their germination ability.
*Author for correspondence.
Journal of Horticultural Science & Biotechnology (2014) 89 (1) 69–73
Variation in Jatropha curcas seed in Benin
MATERIALS AND METHODS
Seeds of J. curcas were collected from each of the ten
phytogeographical districts (phytodistricts) of Benin,
(Figure 1). Ten trees, spaced at least 100 m from each
other to avoid narrowing the genetic base due to
relatedness or inbreeding, were selected and sampled in
plantations in each of the ten phytodistricts, as
recommended by Turnbull (1975). Mature black fruit
(n = 10) were collected directly from each tree.A total of
100 seeds were therefore collected at random in each
phytodistrict.
The colours of the dried seeds of J. curcas were
determined using a standard colour chart (Royal
Horticultural Society, 1966). Seeds were coded 1 if black,
or 0 if brown. The length, width, and thickness of each
seed were measured using electronic calipers. Seed
texture was determined by touch, and coded 1 if rough,
or 0 if smooth. The weight of each seed was measured
using an electronic balance with a sensitivity of 0.0001 g.
Seed length, width, thickness, weight, colour, and
texture data were subjected to an Ascending
Hierarchical Classification (AHC) using SAS statistical
software (SAS, 2003). This enabled classification of the
seeds based on similar morphological traits. Canonical
discriminant analysis was then performed on the
morphotypes identified from the AHC in order to
validate and test the differences between morphotypes.
The clusters (considered to be morphotypes) of J. curcas
seed were also defined by their differences, using
discriminant axes defined by the seed traits being
measured. The same analysis was also performed to test
and describe the differences between the ten
phytodistricts according to the morphological
parameters of the J. curcas seed.
Five morphotypes were identified from the AHC. Five
seeds of each morphotype were sown in a single pot
made from a polythene bag measuring 5.5 cm 18 cm
and filled with forest soil. Ten pots were used for each
morphotype. The experimental units (all pots) were
arranged in a randomised block design with three
replicates. For each morphotype, the number of seeds
that germinated in all ten pots was recorded each day
over a 10 d period. The nursery experiment was carried
out at the University of Abomey-Calavi,located between
6°21’ – 6°42’N and 2°13’ – 2°25’E in the Côtier
phytodistrict, in March 2009 (Figure 1).
The germination percentage of each morphotype of J.
curcas seed was calculated each day over 10 d and used
to measure the effect of time and morphotype on the
rate of germination of J. curcas seed. The statistical test
used was analysis of variance on repeated measures
(Crowder and Hand, 1990) available in SAS statistical
software (SAS, 2003), using the mixed model. In this
model, the factor “block” was considered to be random,
whereas the factor “morphotype” was considered to be
fixed. No data transformation was applied to the
germination percentages because normality and
homoscedasticity were checked without transformation
using the Ryan-Joiner test of normality and the Levene
70
TABLE I
Characteristics of the ten phytogeographical districts of Benin
PChorPhytogeographic district RRainfall (mm) Major soil type Major plant formation
GCR Côtier Bi 900–1,300 Sandy + hydromorphic & Coastal forest and derived thickets,
allomorphic soils mangrove
GCR Pobè Bi 1,200–1,300 Ferralitic soils without concretions Semi-deciduous forest
GCR Plateau Bi 900–1,100 Ferralitic soils without concretions Semi-deciduous forest
GCR Vallée de l’Ouémé Bi 1,100–1,300 Hydromorphic soils Swamp and semi-deciduous forest
SGR Bassila TUn 1,100–1,300 Ferralitic soils with concretions and Semi-deciduous forest, woodland, and
breastplates riparian forest
SGR Zou TUn 1,100–1,200 Ferruginous soils on crystalline rocks Dry forest, woodland, and riparian forest
SGR Borgou-Sud TUn 1,100–1,200 Ferruginous soils on crystalline rocks Dry forest, woodland, and riparian forest
SR Borgou-Nord Un 1,000–1,200 Ferruginous soils on crystalline rocks Dry forest, woodland, and riparian forest
SR Chaîne de l’Atacora Un 1,000–1,200 Poorly evolved & mineral soils Riparian forest, dry forest, and woodland
SR Mékrou-Pendjari Un 950–1,000 Ferruginous soils with concretions Tree and shrub savannahs, dry forest and
on sedimentary rocks riparian forest
PChor, phytochorological zones based on the composition in distribution range types; GCR, Guineo-Congolian region; SGR, Sudano-Guinean
transition zone; SR, Sudanian region.
R, rainfall regime; Bi, bimodal (two rainy seasons);TUn, tendency to unimodal; Un, unimodal (one rainy season).
FIG.1
The ten phytogeographical districts (phytodistricts) of Benin, West
Africa. Inset shows the location of Benin.The black triangle marks the
location of the township of Abomey-Calavi.
0º0'0"E 1º0'0"E 2º0'0"E 3º0'0"E 4º0'0"E
7º0'0"N 8º0'0"N 9º0'0"N 10º0'0"N 11º0'0"N 12º0'0"N
E. A. PADONOU,B.KASSA,A.E.ASSOGBADJO,B.FANDOHAN,S.CHAKEREDZA,R.GLÈLÈ KAKAÏ
and B. SINSIN
test for homogeneity of variances (Glèlè Kakaï et al.,
2006).
RESULTS
Identification of J. curcas morphotypes
Five clusters (morphotypes) were identifed from the
AHC using 54.2% of the information recorded on all
seeds. The results of canonical discriminant analysis
performed on the five morphotypes of J. curcas seed
showed that the Mahalanobis distances between pairs of
the five clusters identified were all highly significant (P
0.001). The morphotypes identified from the AHC were
therefore different according to the morphological traits
of J. curcas seed. Morphotype 1 was derived from the
Côtier, Pobè, The Ouémé Valley, and Plateau
phytodistricts. Morphotypes 2 and 5 were from the
Bassila, Zou, and Borgou-Sud phytodistricts; whereas
Morphotypes 3 and 4 were from Borgou-Nord, the
Atacora Chain, and Mekrou-Pendjari phytodistricts.
Other results from the canonical discriminant analysis
performed on individuals of the five seed morphotypes
revealed that the first two axes were significant (P
0.05) and explained 61.6% of the variation seen in the
morphotypes.The coefficient of correlation between the
two canonical axes (Can) and the morphological traits of
J. curcas seed indicated that the first axis (Can 1)
discriminated the morphotypes according to seed colour,
texture, and weight. On this axis, heavy seeds were also
often black and smooth. The second axis (Can 2)
discriminated the five morphotypes according to the size
of the seed. It showed that long seeds were also wide and
thick.
Seeds from Morphotype 3 and Morphotype 4 were
black, light, and smooth, while seeds from Morphotype 1
were brown, heavy, and rough (Figure 2). Most seeds
from Morphotype 2 and Morphotype 5 were brown,
heavy, and rough, but some were dark, light, and smooth.
The Can 2 axis (Figure 2) discriminated the five
morphotypes according to the size of their seed. For
example,Morphotype 2 and Morphotype 3 differed from
Morphotype 4 and Morphotype 5 according to the
length, width, and thickness of their seed. Seeds from
Morphotype 2 and Morphotype 3 were the smallest. A
more detailed description of each morphotype is
provided in Table II, from which we observed that
Morphotype 5 had the longest seeds (mean = 1.91 cm),
while the shortest seeds were from Morphotype 3 (mean
= 1.77 cm). The widest seeds were found in Morphotype
1 and Morphotype 4 (mean = 1.2 cm), whereas the
thinnest seeds were from Morphotype 3 (mean = 1.08
cm). With regard to seed weight, those of Morphotype 1
were the heaviest (mean = 0.80 g), while the lightest seed
were grouped in Morphotype 2 (mean = 0.66 g).
On the basis of the ten phytodistricts, we noticed that
seeds collected from Mekrou-Pendjari or the Atacora
Chain were black, smooth, lightweight (mean = 0.67 g),
short (mean = 1.76 cm), and thin (mean = 1.15 cm),while
seeds from Plateau, Côtier,The Ouémé Valley, and Pobè
were brown, rough,heavy (mean = 0.84 g), long and wide
(mean length = 1.92 cm; mean width = 1.2 cm). Seeds
from Zou, Borgou-Sud, and Bassila were black, smooth,
and heavy, but some had the opposite features (Table
III).
Germination ability of J. curcas seed according to
morphotype
The germination ability of each seed morphotype
varied over time between sowing and 10 d after sowing
(Table IV). The germination percentages of seeds also
varied throughout the 10 d.The blocking factor and all its
interactions were non-significant, indicating
homogeneity of the environmental characteristics within
and between the blocks.Morphotypes 1, 2, and 3 showed
a rapid increase in germination percentage from 4 d to 10
d after sowing (Figure 3). Morphotypes 4 and 5 showed
less variation in germination percentage over time.
71
FIG.2
Projection of the five morphotypes of J. curcas seed on the canonical
axes defined by morphological traits. Can 1 discriminated on seed
colour, texture and weight. Can 2 discriminated on seed size.
TABLE II
Mean values and standard deviations of traits in the five morphotypes of J. curcas seed
Seed trait Morphotype 1 Morphotype 2 Morphotype 3 Morphotype 4 Morphotype 5
Length (cm) 1. 87 ± 0.091.80 ± 0.12 1.77 ± 0.10 1.85 ± 0.10 1.91 ± 0.09
Width (cm) 1. 20 ± 0.01 1.11 ± 0.06 1.09 ± 0.03 1.20 ± 0.01 1.18 ± 0.07
Thickness (cm) 0.73 ± 0.05 0.71 ± 0.07 0.69 ± 0.05 0.73 ± 0.07 0.98 ± 0.07
Weight (g) 0.80 ± 0.07 0.66 ± 0.16 0.72 ± 0.09 0.71 ± 0.09 0.74 ± 0.11
Colour Brown Black/Brown Black Black Black/Brown
Texture Rough Smooth/Rough Smooth Smooth Smooth/Rough
All values are means (n = 1,000) ± SD.
1. Seed morphotype 1
2. Seed morphotype 2
3. Seed morphotype 3
4. Seed morphotype 4
5. Seed morphotype 5
6. Seed morphotype 6
Can 2
Can 1
Variation in Jatropha curcas seed in Benin
DISCUSSION
Morphological variation in J. curcas seed
This study on the morphological characteristics of J.
curcas seed identified five morphotypes in Benin. These
morphotypes were significantly different according to
their morphological traits, as revealed by canonical
discriminant analysis. This morphological variation in J.
curcas seed was similar to that observed by Ginwal et al.
(2005) in India. Some studies dealing with different plant
species have reported that morphological characteristics
vary with climatic region and ecological gradient.
Maranz and Wiesman (2003) showed a significant
relationship between trait values (e.g., fruit size and
shape, pulp sweetness, and kernel content of the species)
and abiotic variables (e.g., temperature and rainfall) in
sub-Saharan Africa (North of the Equator) for shea
butter trees (Vitellaria paradoxa). Soloviev et al. (2004)
also reported a significant influence of the climatic zones
of Senegal on fruit pulp production in Balanites
aegyptiaca and Tamarindus indica. Therefore, the
phenotypic differences between morphotypes of J.
curcas seed could also be explained by environmental
factors. In fact, apart from the ages and genotypes of the
trees, the soil and climate where they grew were
important factors that affected the morphological traits
of the seed and fruit (Salazar and Quesada, 1987;
Assogbadjo et al., 2005; 2006).
In this study, we noticed that part of the morphological
variation in J. curcas seed could be explained by the
phytodistrict in which the seeds were collected.
Nevertheless, an important overlap between the
provenance of J. curcas seed in Benin has been observed,
indicating that factors other than environment affect seed
morphology. The morphological differences between
seeds could also be of genetic origin, resulting from
adaptation of the species to diverse environmental
conditions (Mathur et al., 1984).This genetic variation, if it
exists, could be an important source for varietal selection.
Seed germination
Rai and Tripathi (1982) reported the positive influence
of a large seed size and seed reserves on the
establishment and early growth of seedlings. In that
respect, one can expect some variation in the rates of
seed germination among the five morphotypes identified
in J. curcas. Indeed, phenotypic variation is generally
assumed to reflect the inherent genotypic variation
among and within groups of plants growing under the
same environmental conditions. In our study, the
germinating ability of J. curcas seed showed significant
variation between morphotypes. The lowest rate of
germination at the end of the experiment was 50%,
recorded for Morphotype 4, while the highest rate of
germination (89%) was recorded for Morphotype 2.This
could reflect genetic variation between these
morphotypes. The differences observed in seed
germination rate could be considered genetic, because
environmental variation at the experimental site was
negligible, and the experimental design reduced any
residual variation that could persist on site. It has been
reported that genotype has a strong influence on seed
vigour (Schmidt, 2000). Since the five morphotypes
consisted of seeds from different sites, the J. curcas
populations we sampled would have restricted gene flow,
which may lead to discontinuous variation in seed
germination characteristics, which are genetically
controlled (Whittington, 1973).
72
FIG.3
Trends in the rates of germination of J. curcas seed according to
morphotype.
TABLE III
Morphometric traits of J. curcas seed from the ten phytodistricts of Benin
PChorPhytodistrict Length (cm) Width (cm) Thickness (cm) Weight (g) Seed colour Seed texture
RGC Côtier 1.85 ± 0.101.2 ± 0.00 0.76 ± 0.08 0.77 ± 0.10 Brown Rough
RGC Pobè 1.86 ± 0.07 1.18 ± 0.03 0.71 ± 0.06 0.83 ± 0.09 Brown Rough
RGC Plateau 1.85 ± 0.11 1.16 ± 0.06 0.77 ± 0.10 0.76 ± 0.11 Brown Rough
RGC Ouémé Valley 1.97 ± 0.05 1.2 ± 0.00 0.76 ± 0.05 0.84 ± 0.12 Brown Rough
SGR Bassila 1.85 ± 0.08 1.16 ± 0.05 0.77 ± 0.12 0.72 ± 0.12 Black/Brown Smooth/Rough
SGR Zou 1.87 ± 0.10 1.16 ± 0.07 0.78 ± 0.13 0.75 ± 0.09 Black/Brown Smooth/Rough
SGR Borgou-Sud 1.81 ± 0.13 1.16 ± 0.05 0.76 ± 0.10 0.74 ± 0.10 Black/Brown Smooth/Rough
RS Borgou-Nord 1.83 ± 0.08 1.15 ± 0.05 0.73 ± 0.00 0.70 ± 0.08 Black Smooth
RS Atacora Chain 1.77 ± 0.10 1.15 ± 0.06 0.74 ± 0.10 0.69 ± 0.10 Black Smooth
RS Mékrou-Pendjari 1.80 ± 0.12 1.16 ± 0.06 0.72 ± 0.08 0.66 ± 0.11 Black Smooth
PChor, phytochorological zones based on the composition and the types of distribution of species; RGC, Guineo-Congolian zone; SGR, Sudano-
Guinean transition zone; RS, Sudanian zone.
All values are means (n = 1,000) ± SD.
TABLE IV
Analysis of variance on repeated measures related to the germination
ability of the five morphotypes of J. curcas seed
Source DFType III SSMean Square F-Value
Time (T) 9 55.58 6.18 1,615.66***
Block (B) 2 0.00 0.01 0.16ns
T x B 18 0.01 0.01 0.17ns
Morphotype (M) 4 3.11 0.78 83.40***
T x M 36 2.34 0.06 17.00***
B x M 8 0.01 0.01 0.07ns
T x B x M 72 0.03 0.01 0.12ns
DF, degrees of freedom.
Type III SS,Type III Sum of Squares; F-value, Fisher value.
ns, non-significant at P0.05; ***, significant at P0.001.
Time after sowing (d)
Germination percentage (%)
Morphotype 1
Morphotype 2
Morphotype 3
Morphotype 4
Morphotype 5
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REFERENCES
... Each class contained 6 to 13 trees depending on the tree population structure at the site. Trees for fruit sampling were selected so they were spaced by at least 100 m apart to avoid the mixing of fallen fruits from different trees and also the consanguinity effect (Padonou et al. 2014). Each tree was geo-referenced and numbered, and the following measurements were recorded: dbh, total height (ht) and crown area (ca). ...
... The observed morphological variations in fruit traits among L. lanceolata trees indicated three shape-groups, which were recorded in both sites. The shape variations cannot be attributed to environmental or climatic factors as reported for some species (Ewédjè et al. 2012;Padonou et al. 2014), because of the homogeneous site conditions in our study area. Other important factors which may affect the fruit morphological traits are the age and the genotype of trees (Assogbadjo et al. 2006). ...
Article
Lophira lanceolata is an important indigenous oil tree species with high socio-economic potential in Africa. This study aimed to assess the fruit production of the species, the impact of infestation on production, and the variability of fruit morphological traits. Thirty mature trees were sampled from each of the two sites in western Burkina Faso. For each tree, all the fruits were collected, counted, dried, and weighed. One hundred fruits were randomly sampled per tree to estimate the infestation rate. 300 fruits collected on 30 trees were sampled to measure their morphological traits. Analysis of variance and regression analyses were performed to test for relationships between fruit production and stem diameter of trees. Results showed that the mean annual fruit production per tree varied significantly among diameter classes, from 0.47 to 8.01 kg dry mass. The infestation rate varied between 3% and 18% of the total fruit production. The prediction model showed a great predictive ability for fruit production (pR2 = 62%) with stem diameter and crown area of trees as explanatory variables. Three shape-groups of fruits were distinguished: spindle-shape (30%), orbicular-shape (19%), and elliptic-shape (51%). Lophira lanceolata has a high fruit production potential with spindle-shaped fruits as the most interesting for exploitation.
... Elles influencent le potentiel séminal édaphique pour le renouvellement des espèces végétales. Ces influences créent un lien entre la morphologie des plantes, leur germination et leur croissance (Padonou et al., 2013(Padonou et al., , 2014. De même, la fonction du sacré assurée par les îlots forestiers constitue une menace pour certaines espèces animales. ...
... Cette idée du maintien de la Myciculture comme AGB prioritaire est similaire à celle de Padonou et al. (2014) qui stipule que certains habitats des espèces de champignon présentent des degrés d´endémisme. La définition de l'aulacodiculture pour le troisième groupe toujours en termes d'AGB prioritaire à travers l'élevage et la commercialisation des aulacodes trouve sa place en ce sens qu'elle occupe la deuxième place des mammifères fréquemment consommés par les populations au sud-Bénin (Padonou et al., 2014). La définition de l'exploitation et la commercialisation du bois énergie pour ce même groupe d'après les résultats de l'AFC convient aux recommandations de Hèdégbètan (2017) pour cette même zone. ...
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Les Aires du Patrimoine Autochtone et Communautaire (APAC) de la Commune de Sô-Ava ont été gérées par des communautés locales qui en faisaient usage et en tiraient des biens et services à leur manière. Pour orienter le mode d’exploitation des ressources forestières par ces communautés locales et garantir la conservation et la gestion durable du Parc Naturel Communautaire de la Vallée du Sitatunga, il est important d’améliorer les conditions de vie de ces communautés en moyens de substance. Le travail a mis en exergue les Activités Génératrices de Bénéfices (AGB) prioritaires pour les communautés gestionnaires des APAC en relation avec les biens et services qu’elles ont tirés de ces ressources naturelles et ce sans les nuire. Les données ont été collectées à partir des entretiens individuels et des focus groups dans les communautés locales autour de huit îlots forestiers dont les biens et services ont été presque les mêmes. Seulement deux îlots forestiers (Kpoémey et Komey) ont continué de fournir des Produits Forestiers Non Ligneux (PFNL) tels que les fruits aux communautés. La disponibilité des champignons, du miel récolté de façon traditionnelle et des escargots a été faible (13,64%) malgré l’utilisation qu’en faisaient les communautés gestionnaires de ces APAC. La définition des AGB prioritaires en fonction des ethnies et par catégorie d’âge a révélé que le groupe des jeunes hommes Ouémè et Aïzo et des jeunes femmes Toffin ont priorisé pour AGB prioritaires l’Apiculture, la Myciculture et l’Achatiniculture. Le groupe composé des jeunes femmes Aïzo et Ouémè, des jeunes femmes et adultes Fon, puis des hommes et femmes âgés Toffin a défini pour AGB prioritaires l’exploitation et le commerce du bois énergie et des plantes médicinales. Le groupe comportant les hommes et femmes adultes Aïzo, les femmes adultes Ouémè puis les hommes jeunes et adultes Fon et Toffin, ont eu pour AGB prioritaires l’exploitation et le commerce du bois d’oeuvre et de service, et des branchages pour Acadja et le commerce de viandes de brousse.
... Research works carried out in Benin and elsewhere (e.g. Cameroon) suggested significant differences in fruit traits between climatic regions (Padonou et al. 2014) and a strong variability of fruit traits within populations than between populations, in particular for cross-pollinated species (Leakey et al. 2005) like B. aethiopum. Furthermore, a strong link is suggested between seeds/fruits size in one hand and their germination and seedling growth (van Mölken et al. 2005). ...
... Similar results were observed on Central Asian Stipa spp. by Hamasha and Hensen (2009) and in Benin for many species including A. digitata , the physic nut (Jatropha curcas L.) (Padonou et al. 2014) and T. indica (Fandohan et al. 2010). In our study, the humid region showed the highest characteristics for hypocotyl parameters compared to sub-humid and semi-arid regions. ...
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Borassus aethiopum Mart. is a multipurpose palm native to mainland Africa. Fruits and hypocotyls are the most exploited parts which collection/harvest threats the species. As a pre-requisite for its domestication, this study assessed the (1) environmental-induced diversity in morphological traits of fruits and (2) differences in growth and weight of hypocotyls from one-seeded, two-seeded, and three-seeded fruits from three provenances in the three climatic regions of Benin. 5400 fruits collected from 180 trees in six populations were measured for fruits and tree morphological traits. A randomized complete block design with three replicates was used for the experimentation in each region. Variation in fruit morphological traits was not influenced by climatic regions. The greatest variation (65–94%) in fruit morphological traits was located at tree level, highlighting that selection of many fruits and individual trees within a few populations would capture large variation of fruit traits. Tree diameter at breast height (18.5–52 cm), total (6.4–19.6 m) and bole (4.8–17.6 m) height, and fruit length (7.00–20.50 cm), dry weight (98–2552 g), shape index (0.59–2.80), and number of seed (1–3) were the most discriminative traits of studied populations. Clustering of the trees resulted into five morphotypes based on discriminating traits. Morphotypes 1 and 2 showed high performances for fruits and seeds production. These morphotypes are good candidates for selection and breeding programs. Irrespective of the provenances, best performances of hypocotyls were observed in the humid region. This study provides important baseline information for the domestication of B. aethiopum.
... Kemampuan berkecambah benih tanaman jarak pagar bervariasi diantara morfotipe, dengan kata lain faktor genetik banyak mempengaruhi perkecambahan tersebut meskipun faktor lingkungan juga berperan (Padonou et al., 2014). Penetesan DNA plasmid pada kepala putik yang diterapkan di metode transformasi langsung melalui jalur tabung polen tidak berpengaruh nyata terhadap hampir semua peubah perkecambahan tanaman jarak pagar genotipe IP3A, IP3P, dan JcUMM18 kecuali saat berkecambah pada genotipe IP3A (Tabel 3). ...
... Perkecambahan pada kondisi lingkungan yang terkontrol dari beberapa morfotipe jarak pagar berkisar 50-89%. Hal tersebut membuktikan bahwa perbedaan perkecambahan benih jarak pagar dipengaruhi oleh vigor benih masing-masing genotipe (Padonou et al., 2014). ...
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em> The genetic transformation via pollen-tube pathway in jatropha is the first alternative method that was applied in this plant. The objective of the research was to study fruit set and germination of three genotypes of jatropha following direct transformations via pollen-tube pathways. The research was conducted during April 2014 until January 2015 at jatropa’s experimental field, Pasuruan, and at green house of ICABIOGRAD, Bogor. Three genotypes of jatropha i.e., IP3A, IP3P and JcUMM18 were used. In the first experiment, split plot design was used where 3 levels of DNA plasmid concentration as a main plot and 5 levels of stigma-drip time of DNA plasmid as a subplot. In the second experiment randomized block design was used with single factor consisting of 15 combinations of concentration and stigma-drip time of DNA plasmid as treatments and control. The results demonstrated that interaction between concentration and application time of DNA plasmid did not significantly affect fruit and seeds formation of three Jatropha genotypes. Combination of DNA plasmid concentration with time of stigma-drip had significant effect on seed germination rate of IP3A genotype, but not significant on the other variables. The concentration of 0.05-0.5 µg µL-1 and application time of DNA plasmid at 1-10 hours after pollination could be applied on jatropha genetic transformation via pollen-tube pathways. Keywords: DNA plasmid, Jatropha curcas, pCAMBIA1301, pollen-tube, stigma-drip </em
... Nous pouvons supposer que l'origine géographique a joué un grand rôle dans la diversité de l'épicarpe des fruits, car la provenance Farako en est une illustration. Ceci a été confirmé sur Tectona grandis en Côte d'Ivoire par [15,16] ont rapporté que la variabilité phénotypique intraspécifique de la plupart des espèces végétales dans les populations naturelles pourrait être un reflet de la variabilité génétique et une adaptation à des conditions environnementales fluctuantes. Le nombre moyen de 5 valves par fruit enregistré dans le cadre de la présente étude a été confirmée par d'autres travaux réalisés dans la galerie forestière qui indiquent que les fruits de Carapa procera peuvent contenir 4, 5 et/ou 6 valves [12,14]. ...
Article
Full-text available
Carapa procera DC est l'une des espèces ligneuses caractéristiques des galeries forestières au Mali. L'espèce est très prisée des populations maliennes pour les soins cosmétiques et médicinaux, mais ses caractéristiques morphologiques sur son aire de distribution au Mali ont été peu évaluées. La présente étude cherche à livrer les descripteurs morphologiques qui discriminent les provenances. L'étude a été réalisée sur 120 arbres, 1200 fruits, 13760 graines et 600 feuilles appartenant à quatre provenances qui sont situées dans la zone soudanienne au Mali. Les mesures ont porté sur les dimensions des fruits, des graines et des feuilles. Les résultats ont montré une faible variabilité entre les provenances pour certaines variables mesurées sur les fruits et les graines. Une forte variabilité entre les provenances a été observée au niveau des variables mesurées sur les feuilles. L'étude a permis de mettre en évidence des différentes formes de fruits et de graines. Les descripteurs morphologiques qui discriminent les provenances de Carapa procera sont la longueur des fruits, la largeur des fruits, la longueur du pédoncule, le ratio longueur/largeur des fruits, l'aspect de l'épicarpe, le ratio longueur/largeur des graines, le poids des graines, la longueur de la feuille, la largeur de la feuille, la longueur du pétiole et la longueur de l'acumen. Ces descripteurs peuvent servir à planifier des analyses génétiques afin de contribuer à une meilleure compréhension de la biodiversité. Abstract Carapa procera DC is one of the characteristic woody species of gallery forests in Mali. The species is highly prized by Malian populations for cosmetic and medicinal purposes, but its morphological characteristics through its distribution area in Mali are not well known. The present study aims to provide morphological descriptors that discriminate the provenances. The study was carried out on 120 trees, 1200 fruits, 13760 seeds and 600 leaves belonging to four provenances that are located in the Sudanian zone in Mali. Measurements were made on fruit, seed and leaf dimensions. The results showed low variability between the origins for some of the variables measured on the fruits and seeds. On the opposite, high variability between provenances was observed for the leaves parameters. The study revealed different fruit and seed shapes. Morphological descriptors that discriminate between Carapa procera provenances are fruit length, fruit width, peduncle length, fruit length/width ratio, epicarp appearance, seed length/width ratio, seed weight, leaf length, leaf width, petiole length and acumen length. These descriptors can be used to plan genetic analyses in order to contribute to a better understanding of biodiversity.
... The sampled shrubs were selected according to five diameter classes (diameter at breast height [dbh]): <3, 3À6, 6À9, 9À12 and 12 cm), with at least 12 shrubs per diameter class in each phytogeographic zone. A distance of at least 100 m was observed between sampled shrubs, to ensure the independence of observations (Padonou et al., 2014;Ou edraogo et al., 2019a). ...
Article
Fruit of Ziziphus mauritiana Lam. are widely harvested by rural communities for food and income across West Africa sahelian areas. The species is listed among the high value food providing plants in Burkina Faso. However, the lack of reliable assessment of its fruit production is one of the main constraints limiting its valorization and sustainable management. This study aims to analyze factors affecting fruit production of Z. mauritiana and to develop allometric models for estimating this production. Total harvest method was used to quantify fruit from 130 individuals distributed into five diameter size classes across two phytogeographic zones of Burkina Faso, the sub-Sahel and the north-Sudanian. Models were fitted with 80% of sampled individuals randomly selected and 20% were used for model validation. The results showed that fruit production varied significantly according to phytogeographic zone and diameter size class. Mean dry mass of fruit per individual was significantly higher (p = 0.0135) in the north-Sudanian zone (1.82 kg per individual; CV = 164.4%) compared to the sub-Sahel zone (1.65 kg per individual; CV = 184.7%). Diameter at breast height and total height of individuals were the best predictors of fruit production in the sub-Sahel zone. For the north-Sudanian zone, Diameter at breast height, total height and crown diameter of individuals were the best predictors. These results provide evidence that allometric models could be used to successfully estimate the amount of fruit production in Z. mauritiana. This is interesting for perspectives of exploitation planning and sustainable management of the species resources.
... Cela peut avoir comme conséquence la faible production de fruits et de graines. Ces résultats corroborent ceux de Soloviev et Gaye (2004) ; Assogbadjo (2006) ; Padonou et al.(2014) et Akabassi et al. (2020 qui ont montré que les variables abiotiques (pluviométrie, température, humidité relative et évapotranspiration) influent significativement les caractéristiques morphologiques des feuilles, fruits et graines du baobab africain (Adansonia digitata) et du Jatropha curcas. ...
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Khaya senegalensis (Desr.) A. Juss. is endemic to many countries in sub-Saharan Africa. The objective of the study was to assess the ecophenotypic characterization of K. senegalensis from the three endemic zones of Chad and the suitability of its seeds to germinate according to provenance for sustainable management.10 leaves, 10 fruits and 270 seeds were collected randomly from 10 K. senegalensis trees per zone. An analysis of variance was performed to compare the morphology of leaves (length and width of leaves) and fruits (length, width, weight and number of seeds) between climatic zones. A germination and growth test followed by repeated measures analysis of variance was performed to assess germination and seedling growth between the three climatic zones. The results revealed that Khaya trees in the Guinean zone had longer and wider leaves and fruits with more seeds than those in Sudanian and Sudano-Sahelian zone. The climatic zone also had a very significant influence on seed germination. The maximum germination rate was obtained for the Guinean zone (78%) on the 21st day and on the 23rd day after germination for the Sudanian zone (77%) and the Sudano-Sahelian (74%). The climatic zone also had a very significant (p < 0.01) effect on growth in height and diameter at the crown. Seedlings from the Guinean zone showed better growth compared to those from the other two zones. Keywords: Khaya senegalensis, ecophenotypic characterization, aptitude for germination, climatic zones, Chad
... Our work showed that GP of J. curcas seed was 83% at 7 days, similarly to seeds collected from Mision Laishi, Formosa, Argentina [21]; whereas the viability (86%) was similarly to reported for seeds from Río Largo, Brasil by Moncaleano-Scandon et al. [23]. In fact, different researches showed that the GP of J. curcas changed according to provenance, for example, between 50% to 89% in seeds from Africa [56], 98.96% in hybrid from Malaysia and Indonesia and 53.43% in hybrid form Cape Verde and South Africa [19]. Also, the germination percentage can varies according to the substrate used for germination test [57], being superior in sand than in clay [58]. ...
Article
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To achieve a good production of a crop, it is essential to know the ability of the species to successfully complete two critical stages in the life cycle such as germination and seedling establishment. In this paper we study in comparative form structure of the seed, the importance of tegument in dormancy, the effect of accelerated aging on seed germination and viability, and the early and late growth in J. curcas and J. macrocarpa. External morphology of the seeds allow difference and internally also the embryos show evident differences. J. macrocarpa germination is around 0%-4%. The total removal of tegument showed a 50% increase and the other treatments between 0%-10%. Aging accelerated by Tetrazolium test allowed a comparative analysis of VP and GP. J. curcas maintains both to 96 h, while J. macrocarpa the seed viability is registered along the all treatment. J. macrocarpa seeds have less synchronicity than those of J. curcas. ABA and JAs were detected in tegument of J. macro-carpa and J. curcas seeds. JA could have a roll in inhibition of germination of J. macrocarpa seeds. Early and late growth, FW and DW of root, hypocotyl, epi-cotyl and leaf of J. curcas were significantly different in both species.
... However, seed germinability varies widely from one provenance to another, depending on the type of dormancy caused by various factors (Bewley 1997;Moussa et al., 1998;Koornnef et al., 2002). Studying dum palm seeds from Niger, Moussa et al. (1998) related variations in seed dormancy to embryo immaturity, seed coat impermeability, and to physiological events during seed storage, as reported elsewhere (Yang et al., 2007;Assogbadjo et al., 2011;Padonou et al., 2014). ...
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Hyphaene thebaica (dum palm) is an important tree species that grows wild in the semi-arid regions of tropical Africa. Increased knowledge on the effect of stress on the propagation and establishment of these plants is needed to optimise its domestication. This study assessed the physical characteristics of H. thebaica fruit harvested from three phytodistricts in Benin. The germinability of the seeds, before and after water-soaking and removal of the seed coat, was tested, and the number and size of the leaves produced in the resulting seedlings were measured. Hierarchical classification of the characteristics of fruit revealed the existence of three morphotypes. A Factorial Discriminant Analysis performed on these morphotypes revealed highly significant differences (P ≤ 0.001). Morphotype 3 (48 seeds) had the highest rate of seed germination (49.99%) and the widest leaves (28 mm) over the 154 d of the experiment. Seedlings of morphotype 2 and morphotype 3 (48 seeds each) had the highest number of leaves (two per seedling), whereas only morphotype 2 seedlings had the longest leaves (35 mm). Results from Analysis of Variance revealed that the time of germination and water-soaking had significant effects (P ≤ 0.05) on seed germination. The study also showed that the growth of seedlings differed with the time of germination, and that these differences varied with morphotype. These results may be used to improve current propagation and conservation strategies in this species in its areas of origin.
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The current study was conducted in 2013 to identify the seeds of three species of Amaranthus , Amaranthus viridis L., Amaranthus retroflexus L. and Amaranthus albus L., by using the artificial neural network (ANN) and canonical discriminant analysis (CDA) methods. To begin with, photographs were taken of the seeds and 13 morphological characteristics of each seed extracted as predictor variables. Backward regression was used to find the most influential variables and seven variables were derived. Thus, predictor variables were divided into two sets of 13 and seven morphological characteristics. The results showed that the recognition accuracy of the ANN made using 13 and seven predictor variables was 81.1 and 80.3%, respectively. Meanwhile, recognition accuracy of the CDA using the seven and 13 predictor variables was 74.0 and 75.7%, respectively. Therefore, in comparison to CDA, ANN showed higher identification accuracy; however, the difference was not statistically significant. Identification accuracy for A. retroflexus was higher using the CDA method than ANN, while the ANN method had higher recognition accuracy for A. viridis than CDA. In addition, use of 13 predictor variables yielded a greater identification accuracy than seven. The results of the current study showed that using seed morphological characteristics extracted by computer vision could be effective for reliable identification of the similar seeds of Amaranthus species.
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The aim of the study was to determine source variation in Jatropha curcas seeds collected from ten locations in Central India. A significant seed source variation was observed in seed morphology (colour, size and weight), seed germination (viability, germination percent, germination energy, germination value) and seedling growth parameters (survival percentage, seedling height, collar diameter, leave/plant, and seedling biomass). The seed source of Chhindwara (M.P.) was found as the best source in comparison to others. The phenotypic and genotypic variance, their coefficient of variability and broad sense heritability also showed a sizeable variability. This offers a breeder ample scope to undertake screening and selection of seed sources for the desired traits. Further, high percentage of heritability coupled with moderate intensity of genetic gain, was observed for seed germination traits, which signifies that germination is under strong genetic control and good amount of heritable additive genetic component can be exploited for improvement of this species.
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RESUME La présente étude a pour objectifs de faire des évaluations ethnobotanique et écologique de Jatropha curcas en vue de sa meilleure valorisation au Bénin. Les enquêtes ethnobotaniques ont été réalisées sur 37 groupes ethniques et ont concerné 70% des Communes du Bénin. La caractérisation écologique a porté sur la description des habitats de l'espèce, sa distribution, ses caractéristiques morphométriques et ses relations avec l'environnement. Les populations utilisent beaucoup plus les feuilles de J. curcas pour traiter les maux de ventre, les maladies du foie, l'ictère, la gonococcie et, le paludisme. La sève est utilisée dans le traitement des morsures de serpents, de la mauvaise haleine et de l'hémorragie. Les graines sont par ailleurs utilisées comme purgatif. Les variables dendrométriques et les niveaux de rendement de l'espèce diffèrent significativement entre individus de différents Départements. L'espèce pousse sur une gamme variée de sol. Les variables abiotiques pH eau , pH kcl , carbone organique ou matière organique n'influencent pas les caractéristiques morphologiques et la productivité de J. curcas dans les conditions de production traditionnelle. Toutefois, il a été remarqué que les zones présentant un climat humide et chaud ou celles caractérisées par des sols sableux sont celles dans lesquelles les individus de J. curcas sont peu productifs. INTRODUCTION Malgré la richesse de la biodiversité du continent africain, l'agriculture rencontre de nombreuses difficultés qui entravent son développement économique et le bien-être des populations. La résolution de ces problèmes passe entre autres par la diversification de l'agriculture à travers la valorisation de toutes les ressources et le développement de nouveaux systèmes de production durable. Ceci nécessite une meilleure connaissance du potentiel des ressources naturelles disponibles et déjà intégrées dans les habitudes culturelles des populations rurales. Ainsi, nombreux sont les auteurs qui s'intéressent de plus en plus à l'évaluation et à la valorisation des ressources phytogénétiques. Au nombre de celles-ci, le pourghère ou pignon d'Inde (Jatropha curcas L.) est une espèce d'Euphorbiaceae à usage multiple utilisée par les populations rurales dans la médecine traditionnelle et comme haie vive dans le bornage des habitations. L'espèce a connu ces dernières années un regain d'intérêt surtout à cause de son utilisation comme biocarburant. En effet, le réchauffement planétaire occasionné par les gaz à effet de serre se manifeste de plus en plus par ses effets néfastes sur le milieu de vie humain ce qui nécessite la recherche de sources d'énergie alternative et renouvelable. L'Europe s'est fixée comme objectif de substituer 5% de ses utilisations de pétrole par des énergies renouvelables d'ici 2010 (Shanker et al., 2006). En conséquence, nombreuses sont des études qui ont porté ces dernières années sur divers aspects liés à
Article
Introduction. Adansonia digitata L., Balanites aegyptiaca (L.) Del. et Tamarindus indica L. figurent parmi les especes fruitieres de cueillette les plus appreciees par les populations sahelo soudaniennes. Leur role sur le plan nutritionnel et sur la generation de revenus est important. La degradation des ecosystemes constitue une menace sur la ressource en fruits de cueillette et sur la diversite genetique de ces especes. La premiere etape du programme de domestication mis en œuvre au Senegal consiste a en caracteriser la variabilite naturelle, dans le cadre d'une demarche participative visant la selection d'accessions interessantes pour la qualite des fruits. L'objet de cette etude a ete de comparer, pour chacune des especes, les fruits de differentes accessions. Materiel et methodes. Les analyses ont porte sur une caracterisation biometrique des fruits, completee par une analyse chimique sommaire (eau, sucres solubles totaux, acidite libre totale). Resultats et discussion. Pour la totalite des criteres etudies, l'exploitation des donnees a montre des differences significatives entre les accessions au sein de chaque espece. Pour les caracteres biometriques, un gradient decroissant de variabilite apparait selon la sequence: Adansonia vers Tamarindus vers Balanites. Le critere de « valeur reelle de la pulpe » a permis de cibler des accessions plus interessantes que d'autres. Les caracteres chimiques ont presente une moindre variabilite. Conclusions. Les differentes accessions etudiees presentent une variabilite exploitable pour la diffusion aux populations locales de varietes performantes d'especes fruitieres repondant a leurs besoins et a leurs moyens.
Article
This study was carried out in the Sudanian (9°45'–12° N), Sudano-Guinean (7°30'–9°45' N) and Guinean (6°25' – 7°30' N) zones of Benin. The distribution and relative abundance of the baobab was studied by means of megatransects and by surveying a number of selected sites. In each zone, an estimate was made of pulp, seed and kernel production from 1200 fruits harvested from 30 individuals. In the Sudanian zone and in some regions of the Dahomey-Gap in the Guinean zone, a population density of 5 baobabs per km2 was recorded. In the Guinean zone, a density of only 1 baobab per km2 was recorded. The baobab population's occurred on sandy soils in the Sudanian and Guinean zones and on sandy–clayey soils in the Sudano-Guinean zone. Flowering and fruiting of the baobab is seasonal. The morphology and productivity of individual baobabs varied significantly from one zone to another. The zones with high values of potential evaporation, rainfall, relative humidity, temperature, pHwater and percentage of fine silt are associated with a low seed and fruit pulp production. The higher the pHKCl, the percentage of total nitrogen, organic carbon and organic matter, the higher the number of seeds produced by an individual baobab. The higher the clay and crude silt content of the soil, the better the productivity.
Article
Aim  Woody vegetation patterns in African savannas north of the equator are closely connected to human presence, but the distinctions between natural and anthropogenic landscapes have not been clear to many observers. Criteria for identifying savanna landscapes on a continuum of intensity of anthropic impact are explored.Methods  A key savanna tree species, Vitellaria paradoxa (Sapotaceae), was used as model for evaluating anthropic impact. Fruits harvested from tree populations across the species range were analysed for variation in traits valued by indigenous peoples. A simple selection index was used to scale tree populations from a hypothetical wild state to a hypothetical domesticated state. Index values were compared with trait values along climate zone gradients and evaluated in the context of indigenous savanna management practices and historical species distribution reports.Results  Trait values such as fruit size and shape, pulp sweetness, and kernel fat content show a significant influence of temperature and rainfall. At the same time, the mean values of groups of traits vary perpendicular to the general climatic zone gradient. Selection index values between Vitellaria populations vary up to sixfold, with highest values in central Burkina Faso. Comparison of present day Vitellaria distribution with historical range limits show range expansion by human migration.Main conclusions  The prevalence of major economic tree species in the savannas of Africa north of the equator is a strong indicator of human involvement in tree dispersal. This conclusion is supported by paleobotanical evidence and by recent Vitellaria range expansion as a result of human migration. The presence of high mean values of several Vitellaria fruit traits in central Burkina Faso suggests that selection for desired characteristics has occurred. The impact of indigenous savanna peoples on woody species composition and spatial distribution is probably much greater than usually thought and is the result of a deliberate strategy of altering the landscape to provide needed human resources.